Six products, each earning its complexity for one specific shape.
Cloud SQL is the baseline every other row is measured against.
ProductCost vs SQLJustify by
AlloyDB~1.5-2xMeasured analytical/transactional bottleneck
SpannerMaterially higherGlobal distribution + strong consistency, both needed
BigtableNode-basedMassive-scale throughput/latency, no SQL needed
BigQueryScan-basedAnalytical queries over large historical data
Spanner's global distribution + strong consistency has no truly direct AWS equivalent — a genuine GCP differentiator, not just a naming difference.